Study of microencapsulated pituitary transplantation. Preparation of the capsule and its property

Microencapsules for pituitary transplantation was successfully developed with sodium alginate and poly-L-lysine (average molecular weight MW 70,000). The permeability of the capsular membrane (CM) was tested. The results showed that 60% of growth hormone (GH), thyroid stimulating hormone (TSH), prolactin (PRL) have passed through the membrane within 3 hours, and reached equilibrium up to 6 hours, suggesting that pituitary hormones (MW 20,000) could pass through CM freely. Bovine serum albumin (MW 67,000) in 50% could also permeate the CM in 3 hours and reached equilibrium up to 24 hours. While immunoglobulin (Ig, MW > 150,000) did not penetrate the CM completely. This study revealed that the microencapsular membrane we made effected immuno-isolation and could be used for pituitary transplantation.